A garnish is provided with a protrusion portion which protrudes outwardly, in a vehicle width direction, so as to suppress a side-face airflow flowing below a door maximum-width portion of a side portion of a cabin from going around below a vehicle floor. A plate-shaped tire deflector is provided at a lower end portion of a front edge of a rear wheel house which corresponds to a position, in a vertical direction, of a rear end portion of the protrusion portion, wherein the tire deflector is configured to deflect a side-face airflow flowing above the protrusion portion such that the side-face airflow is turned toward an outward side, in the vehicle width direction, so as not to flow into the rear wheel house and adheres to a tire-wheel outer face.